How do oysters reproduce

The fertilized eggs develop inside the female for about 10 days before being released into the environment. The larvae then become part of the planktonic community, floating with the currents and tides. After approximately three to four weeks, the larvae metamorphose to their juvenile form and are ready to settle on and attach to a hard substrate, such as oyster reef balls, rip rap along the shoreline, or scientific monitoring devices.

If the oysters are able to find a hard substrate which can be difficult and thus the reason for our native oyster restoration efforts , they attach themselves and will hopefully remain there to live out their lives.

Employment Opportunities. Skip to main content Skip to primary sidebar Skip to footer. By Chris Lim Birds do it. Bees do it. Within six hours, fertilized eggs develop into larvae, which become fully shelled within 12 to 24 hours and are ready to attach themselves to a solid substrate within three weeks. Some species of oysters have separate sexes, but their reproductive organs contain both sperm and eggs.

They are able to change sex from year to year. Some oysters are hermaphrodites and theoretically can fertilize their own eggs. When food is abundant, females are prevalent, but when food is scarce, there are more males.

Spawning is temperature-dependent, and occurs at 68 degrees Fahrenheit. Staff patiently watch this process, identifying spawning oysters from the table and separating them by sex. This is done to collect the eggs and the sperm, get a diverse genetic gene pool, and to prevent polyspermy, when too many sperm fertilize one egg. Males will emit a continuous flow of sperm from the dorsal side of their shell, while females clap their valves together to release eggs in a puff from the front of their shells.

Females can clap every 30 seconds up to an hour, producing anywhere from 2 to 70 million eggs per spawning event. One spawning event can last up to one hour. Once the spawn is finished, the adults are carefully removed from the spawning tubs and measured. The egg mixture is transferred into a large bucket and diluted with filtered ambient water at the correct salinity and temperature.

The eggs are counted using a microscope to tally the number of eggs found in one milliliter of the diluted egg mixture. Once the estimated number of eggs is determined, the proper amount of sperm is added to the buckets. The eggs will be allowed to fertilize for ten minutes and will be checked to see how they progress under the microscope. And now, the hatchery has oyster larvae, which will be fed and grown for weeks, issuing in another phase of the oyster development process.